Feed mechanism in sewing machine



Sept. 23, 1969 SHOJI SHIMOBAYASHI 3,468,272

FEED MECHANISM IN SEWING MACHINE Filed Nov. 9, 1967 SH 03' SHIMOBAYASHI "mum:

United States Patent 3,468,272 FEED MECHANISM IN SEWING MACHINE Shoji Shimobayashi, Kyoto, Japan, assignor to Aisin Seiki Kabushiki Kaisha, Kariya, Aichi Prefecture, Japan Filed Nov. 9, 1967, Ser. No. 681,617 Claims priority, application Japan, Nov. 14, 1966, 41/ 74,812 Int. Cl. Db 27/12 US. Cl. 112-212 1 Claim ABSTRACT OF THE DISCLOSURE This invention relates to a mechanism for feeding fabric in a sewing machine, comprising a rotary vertical shaft driven from a conventional driving means in the sewing machine and mounted with its lower end being oscillated frontwardly and rearwardly by said driving means, and a rotatable feed roller on the lower end of said rotatable and oscillatable vertical shaft, the axis of which feed roller being reciprocated frontwardly and rearwardly while the feed roller is rotated in one direction around its axis at a position adjacent the presser foot of the sewing machine to provide an intermittent feeding of the workpiece.

The principal object of the invention is to provide a new feed mechanism which is reliable in operation and is suited for any desired feed under various speed of operation of the sewing machine.

Other objects and advantages of the invention will become apparent from the following description, when taken in conjunction with the accompanying drawings in which:

FIGURE 1 is a perspective view of the feed mechanism of sewing machine according to the present invention; and

FIGURE 2 is a schematic view of the feed roller for the purpose of illustrating the manner of its operation.

Referring to FIG. 1, a usual driving pulley 2 on the machine arm 1 is connected to a pulley 4 mounted on one end of a horizontal shaft 5 through a timing belt 3. Rotation of said shaft 5 is transmitted through a gear 6 consisting of a worm and worm wheel (not shown) to a vertical shaft 7. At upper end of the shaft 7, there is securely mounted a step pulley 8 which is connected to another step pulley 9 through a belt 10. A vertical shaft 11 of said pulley 9 is rotatably mounted in a sleeve 11' which is slightly inclined, for about 70 relative to the horizontal direction of feed of the fabric, and is oscillatable frontwardly and rearwardly. The lower end of the oscillatable vertical shaft 11 has a bevel gear 12 meshing with a bevel gear 13 on a short axis 14 having securely mounted thereon a feed roller 15 which is arranged adjacent the presser foot of the sewing machine as shown.

At the other end of the shaft 5, there is connected a reciprocable vertical arm 16' as by means of, for instance, an eccentric disc-and-strap connection, and the lower end of said arm 16' is pivoted to the end of the upper arm 17 of a bellcrank lever 17-18 pivotally mounted on the machine arm. The lower arm 18 of said bellcrank lever is provided with an oblong slot 19, and the side edge thereof has a suitably graduated scale. A horizontal arm 20 extending from the sleeve 11' has a pin inserted into the oblong slot 19 of the lower arm 18 of said bellcrank lever, the arrangement being such that according to oscillation of the bellcrank lever 17-18 the sleeve 11' together with the gertical shaft 11 will be oscillated frontwardly and backwardly. The magnitude of the oscillatory movement of the shaft 11 may be adjusted by varying the position of connection of said pin on the end of the arm 20 in the oblong slot 19 based on Patented Sept. 23, 1969 the scale 19. 23 is a spring tending normally to maintain the bellcrank lever 17-18 turned in the counterclockwise direction.

The operation of the mechanism of the present invention is as follows: Upon starting the operation of the sewing machine, driving the driving pulley 2 as usual, the feed roller 15 will be rotated in the direction of arrow as driven through the timing belt 3, the shafts 5 and 7, the step pulley 8, the belt 10, the pulley 9 and the vertical shaft 11. At the same time, the bellcrank lever 17-18 will be reciprocated in the clockwise and counterclockwise directions, so that the arm 20 will be reciprocated, whereby said feed roller 15 will be reciprocated frontwardly and backwardly while being rotated around its axis 14. Thus, it will be understood that the feed mechanism performs the pitch feed by means of the oscillatory movement of the bellcrank lever 17-18 as well as the pitch feed by means of the rotation of the feed roller 15 around its axis, the oscillatory movement of the bellcrank lever in the counterclockwise direction performing the return motion of the axis of the feed roller 15, and such feed motion is repeated.

For the given speed of rotation of the driving pulley 2, the speed of rotation of the feed roller 15 may be adjusted by effecting the desired speed change with respect to the step pulleys 8 and 9 connected by the belt 10. The feed of the fabric by the reciprocal movement of the axis 14 of the feed roller 15 may be adjusted by adjusting the point of connection of the end pin of the arm 20 along the oblong slot 19 of the lower arm 18 of the bellcrank lever 17-1 8. In FIG. 2,'assuming that the fabric is fed for one pitch A of 2 mm. by the rotation of the feed roller 15, while the feed of one pitch B, 2 mm., is effected by the forward movement of the axis 14 of said feed roller 15, thereby two pitch feed C will be effected during one rotation of the sewing machine, whereas by rearward movement of the axis 14 the return feed of one pitch will be effected, during which the fabric will be stopped. The above mentioned feed operation will be repeated, and will be effected in synchronism with the What I claim is:

1. In a sewing machine having a frame with an overhanging arm carrying sewing instrumentalities and a presser foot, and drive means, a feed mechanism including a substantially vertical rotary shaft, means mounting said shaft on the end of said overhanging arm for oscillation forwardly and rearwardly along the line of work feed, means connecting said drive means to said shaft for constant rotation thereof, a feed roller mounted on the lower end of sand shaft and driven thereby, means driven by said drive means and coupled to the lower end of said shaft to impart oscillatory motion to the lower end of said shaft adjacent the presser foot, whereby a workpiece is intermittently fed forward by the rotation of said feed roller combined with the forward oscillation of the lower end of said shaft.

References Cited UNITED STATES PATENTS 2,197,255 4/1940 Kucera 112-214 2,875,716 3/ 1959 Pinkvoss 112-211 2,976,831 3/ 1961 Hacklander 112-214 X 3,094,088 6/1963 Di Camillo 112-211 ALFRED R. GUEST, Primary Examiner US. Cl. X. R. 

